Patent GB-1362691-A (GB)
Title: Grinding wheel dressing apparatus
IPC: B24B53/06
Filed: 1972-02-15
Abstract: 1362691 Dressing grinding wheels A A JONES & SHIPMAN Ltd and J HOULDSWORTH 15 Feb 1972 [5 Feb 1971] 3996/71 Heading B3D A grinding wheel dressing apparatus comprises a tool holder 10 which is adapted to carry a cutting tool 7 and is pivotally mounted 12 intermediate its length on a carrier member 13 itself mounted to rotate about an axis XX at right-angles to the pivotal axis of the tool holder, biasing means 18, 20 arranged to urge the tool holder to a central rest position with respect to the member, input means 22, 24 carried by the member, connected to the end of the tool holder remote from the tool, and arranged so that operation thereof initially causes the carrier member to turn about its axis to move the tool in an arcuate cutting path, the tool holder remaining stationary with respect to the member, and adjustable stop means 29 arranged to arrest the member to terminate the arcuate cutting motion, continued operation of the input means causing the tool holder to turn on its pivot against the biasing means with the member stationary so that the tool performs a substantially straight cutting motion. The apparatus can be used to dress the grinding wheel so as to have a convex or concave profile with substantially straight portions on each side. The holder 10 has an arm 8 which carries the cutting tool 7 and is radially adjustable along guides 9 on the holder. A pin 12 pivotally supports the holder in the carrier member 13 which is mounted in bearings 14 in a body 15. The member and holder are formed with surfaces R, Q against which a pin 19 is pressed by springs 18 mounted in the member 13 and a spring 20 mounted in the holder 10 whereby the holder is biased about pivot 12 to a central position in which arm 8 is parallel to axis XX. The inner end of the holder is formed with a gear segment 25 which engages a gear 24 rotatably mounted on the member 13 and connected to a handle 22 or motor. Adjustable stops 29 are provided in a T-groove in the member 13 and co-operate with an abutment 30 on the body 15. In use, starting from the central position, rotation of handle 22 rotates member 13 and holder 10 about axis XX to cause tool 7 to dress the arcuate profile until one of the stops 29 engages abutment 30 to prevent further rotation of member 13. Continued rotation of handle 22-rocks holder 10 about pivot 12 so that the tool dresses one of the substantially straight portions. Rotation of the handle in the opposite directions returns the tool to its central position for dressing the remainder of the arcuate portion and the other substantially straight portion. For dressing concave profiles, the member 13 is rotated until the gear 25 is in the position 36. In another embodiment, diametrically opposed gears 25 are provided and the gear 24 is mounted within an eccentric bush so as to be engageable with one or the other gears for dressing concave or convex profiles. The pin 12 may be in two parts and mounted in ballbearings. Dust may be prevented from entering the apparatus by a part-spherical shell (45, Fig. 10, not shown) on the holder engaging a wiper (47) in the carrier member. Sliding blocks (53) may take up the load between the gears.